RATRACER Posted March 9, 2009 Share Posted March 9, 2009 Hello, can anyone offer any advice as to pit falls or problems when replacing 300 tdi head gasket? My engine has done 78000 mls and is blowing at back off the head,but losing no coolant(as yet),but it,s getting louder. A distinct chuffing noise that can also be felt when you put your hand to the back of the cyl.head by the bulkhead. Is this a common problem? Thanks in anticipation............RATRACER. PS. new exhaust gasket fitted friday,so its not that,or the injector washers,any other suggestions welcome. Quote Link to comment Share on other sites More sharing options...
Typsey Posted March 10, 2009 Share Posted March 10, 2009 Have you completely ruled out a leaking injector gasket? Just a thought before going into the problems of a head gasket change. We have recently done mine and found the Haynes manual was perfectly good for the purpose. If you don't do anything else, make sure you follow the guide on undoing and redoing up the head. You do not want to inadvertantly warp it because you got impatient. Quote Link to comment Share on other sites More sharing options...
bushwhacker Posted March 10, 2009 Share Posted March 10, 2009 Hi. I hav,nt checked but there maybe a tread on here on how to do a 300 head gasket. I have used help from this site many times and been able to manage a good number of fixes ie 110 clutch, 110 head gasket, 200 head gasket, series 2/3 brakes, plus the removal of a few redunant parts. There is more but I would like to for get them As Typsey says the undoing and redoing of the head bolts is important. Two useful things to have to keep the new gasket in place are 2 old head bolts with the top of and slotted for a screwdriver. It helps when mating the head up and keeping the new gasket in the right place. Good Luck Quote Link to comment Share on other sites More sharing options...
rocky Posted March 10, 2009 Share Posted March 10, 2009 Hi, i did mine a few months ago, had the head pressure tested and skimmed. I follwed advice on this forum and with a haynes manual. I used a genuine landrover headgasket and have had no probs since, over 3000 miles. Regards, rocky Quote Link to comment Share on other sites More sharing options...
steve58 Posted March 17, 2009 Share Posted March 17, 2009 You should use new head bolts every time you replace the head on these engines because they can stretch permanently. Also it's a good idea to run a thread tap down all the head bolt holes to clean them out and make sure there is no excess oil or water in the threaded holes (blow them out with an air line after you have cleaned the threads - wear safety goggles). At least apply oil or light grease under the head of each bolt as well as the threads of the bolt before fitting-tensioning them as well. Make sure the head gasket surface area is spotlessly clean and devoid of any old gasketing material. Clean the top of the engine block with a flat new oil stone as well. Get the head checked for hardness, there is a simple check that your local engine rebuilder should be able to do (takes less than a minute). Check your cylinder head with a straight edge (not a ruler) and a .002" feeler strip (a human hair or tally-ho paper is 004" and is to thick!) for flatness longitudinally, diagonally and across the narrow dimension of the head gasket facing area for true flatness of the gasket surface area. If you can fit a .002" feeler strip at any place between the straight edge and head gasket surface get the head resurfaced in a mill with a PCD finishing cut then check for flatness again. PCD (Poly Crystaline Diamond) can be used on these heads because they don't have precom chambers, and that PCD tip will easily give a mirror finish which is always needed particularly on metal laminate gaskets. Use a good tension wrench and follow the head gasket manufacturers torque pattern and tension guides, not haynes manuals, because IMO haynes manuals are not worth a crumpet. If the gasket you have bought did not come with the torque guide your using an inferior gasket. Hope that helps point you in the right direction. Cheers Hello,can anyone offer any advice as to pit falls or problems when replacing 300 tdi head gasket? My engine has done 78000 mls and is blowing at back off the head,but losing no coolant(as yet),but it,s getting louder. A distinct chuffing noise that can also be felt when you put your hand to the back of the cyl.head by the bulkhead. Is this a common problem? Thanks in anticipation............RATRACER. PS. new exhaust gasket fitted friday,so its not that,or the injector washers,any other suggestions welcome. Quote Link to comment Share on other sites More sharing options...
BogMonster Posted March 17, 2009 Share Posted March 17, 2009 You should use new head bolts every time you replace the head on these engines because they can stretch permanently. The workshop manual says they can be used a maximum of five times however the obvious risk in any older vehicle is not knowing how many times they have been used before ... it certainly doesn't hurt to change them it just costs a bit more. Quote Link to comment Share on other sites More sharing options...
steve58 Posted March 17, 2009 Share Posted March 17, 2009 Generally speaking, worldwide engine re-building practice suggests that torque to yield type head bolts (those that are tightened with angular reference as well as with a tension wrench) should be replaced because bolts stretch. That becomes even more important in countries with extreme weather temperatures at both ends of the scale. If a person can't afford to replace the head bolts, the next best thing is to compare the measurement of the intended reused head bolts to a new set to make sure the lengths are very close before refitting them. Because of the extra cost, the vehicle owner ultimately has to make the decision as to whether to risk having to redo the job because of a failure possibly due to reused old head bolts. A common reason used by head gasket manufacturers to not warrant head gaskets is if the head bolts are not replaced. The workshop manual says they can be used a maximum of five times however the obvious risk in any older vehicle is not knowing how many times they have been used before ... it certainly doesn't hurt to change them it just costs a bit more. Quote Link to comment Share on other sites More sharing options...
BogMonster Posted March 17, 2009 Share Posted March 17, 2009 I'm not arguing with you, and in fact myself tend to work on the basis of when in doubt replace, I just quoted what the manufacturer of the vehicle put in their official workshop manual. Erring on the side of caution is rarely a bad thing Quote Link to comment Share on other sites More sharing options...
Les Henson Posted March 18, 2009 Share Posted March 18, 2009 If the workshop manual says the bolts can be used up to 5 times, then they can and are clearly designed to do that Why replace something that doesn't need replacing? The chances of a set of bolts already being used 5-times is a bit remote, but therein lies the only risk. Les. Quote Link to comment Share on other sites More sharing options...
steve58 Posted March 18, 2009 Share Posted March 18, 2009 BogMonster I did not take your reply as an argument at all. Likewise this reply to you is not meant as an argument or criticism, so please don't take it that way. Referring to your quote from the manual of 5 uses is OK for the head bolts, did you initially read that in a Haynes manual by chance? The reason I ask that is from my personal experience I believe Haynes manuals are a waste of money and riddled with misinformation. Maybe Haynes are good for general service routines etc but anything more involved regarding engine reassembly or parts there of I would not take as a definitive guide or recommend same. The Land Rover factory supplied manual on the other hand as 1 would expect is very accurate in most details. Interesting thing is that the LR factory manual that I DL via the links as a PDF, states to discard the head bolts after removal. The head bolt suggestion I made may not solve the OP's problem, however, he can certainly look into it if he so chooses. The original reply I made to the OP merely skims the surface as far as his problem is concerned, hopefully he will get a fix soon. Because I initially joined this forum to get information regarding the appalling ABS braking issues with my recently purchased Discovery 1, and at the same time read about some other very beneficial information (Particularly from Les Hensons tutorials - Thanks), I wanted to pass on some of my information that in this case may be helpful to the OP. As a mechanic for the first 5 years of my working life, and as an engine reconditioner,builder & machinist hands on for 25 years since then, I may have some knowledge that may assist some others that are having issues regarding engines. After all, as sections on this very forum display so much helpful information, knowledge should be shared, you can't take it with you. Cheers I'm not arguing with you, and in fact myself tend to work on the basis of when in doubt replace, I just quoted what the manufacturer of the vehicle put in their official workshop manual. Erring on the side of caution is rarely a bad thing Quote Link to comment Share on other sites More sharing options...
BogMonster Posted March 18, 2009 Share Posted March 18, 2009 What I wrote came from the factory workshop manual as provided on the RAVE CD-ROM's, so interesting to hear that your version seems to be different! Haynes manuals are ok but I prefer to use the genuine manuals where available though even those are not infallible. Quote Link to comment Share on other sites More sharing options...
cipx2 Posted March 18, 2009 Share Posted March 18, 2009 From the 300tdi Overhaul section on the Discovery 1 RAVE cd: Quote Link to comment Share on other sites More sharing options...
steve58 Posted March 18, 2009 Share Posted March 18, 2009 I don't want to flog a dead horse, and I'm not interested in proving myself right or anyone else wrong regarding this matter. I've attached the torque chart for the 300TDi which clearly shows the torque to yield settings of the head bolt tensions. Sorry everybody concerned, but torque to yield head bolts ARE NOT REUSABLE because they ALWAYS stretch, and no, they don't go back to their original length when you undo them. If you do reuse them, use them at your own peril. Thanks cipx2 for your post regarding the manual, saved me doing it as well. Cheers From the 300tdi Overhaul section on the Discovery 1 RAVE cd: Quote Link to comment Share on other sites More sharing options...
BogMonster Posted March 18, 2009 Share Posted March 18, 2009 Neigh!! From the Defender 300Tdi workshop manual, I wasn't making it up the Discovery 300Tdi workshop manual says the same, max five times. The overhaul manual I have says what you posted, to use new bolts. So we were both right - Land Rover recommend that if you are OVERHAULING an engine you should fit new bolts (makes sense if it is supposed to be an as-new rebuild from the ground up) while if you are just removing the head for some other reason you can re-use them. I don't dispute your logic about why they shouldn't be re-used (permanent deformation) but the Tdi isn't the only engine that says you can according to the book - we rebuilt a Mermaid marine diesel at work a few months back and they were supposed to be re-usable up to three times according to the book. However ... the rebuilt engine also blew a head gasket soon afterwards and once rebuilt with new head bolts it was fine... draw own conclusions as to the validity of what is said in manufacturers literature!!! Quote Link to comment Share on other sites More sharing options...
steve58 Posted March 18, 2009 Share Posted March 18, 2009 Maybe the manuals were written by women and they can't make their mind up? It's not my logic, rather fact of physics, you stretch a head bolt, it gets thinner, hence when 1 reuses it, it's not as strong as it was originally designed to be. One of the points of having torque to yield head bolts and laminate single metal type head gaskets particularly in high compression diesel engines and hi tech petrol engines is to reduce cylinder bore distortion and hence questionable ring seal with the cylinder walls. That's another very technical issue and I'm not going to go into that here and besides I'm finished with this topic. I'm out of here. CU Quote Link to comment Share on other sites More sharing options...
Les Henson Posted March 18, 2009 Share Posted March 18, 2009 Because a head bolt gets thinner, it doesn't necessarily follow that it can no longer do the job it's designed for. A lot of stretch bolts have a max length measurement that you take in oder to determine if it's still ok to use (Freelander 1.8i for example). Les. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted March 18, 2009 Share Posted March 18, 2009 Ok Either how about only using 2.5x ....all happy now ? or better still a nice V8 with ARP Head studs ....even better Hope this helps Nige Quote Link to comment Share on other sites More sharing options...
RATRACER Posted March 18, 2009 Author Share Posted March 18, 2009 WOW, Never would have thought it could be so complex/controversial issue. Have now fitted new gasket with help from the wife and kids,advice from forum members(thank you all) and,horrors of horrors I used the Haynes manual torque sequence and settings,and the same bloody bolts. Now worried, as although it was not too technical a job, it was hard work , and the thought of doing it again fills me with dread! It's run well for 50 miles and fingers crossed............... once again thanks for input.............RATRACER. Quote Link to comment Share on other sites More sharing options...
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